Prayers in Uman: Rabbi Nachman is said to have promised to pull a man out of Hell by his sidelocks if he should come to his grave and repent at New Year (Credit: AFP/Getty images)

The Rabbi would sit cross-legged in the hovels of the Jews and throw greasy morsels and bones from his food to them before reciting the psalms of their ancestors. While he rocked back and forth, they would scuffle for these holy scraps. The Jews were rapt to his hypnotic words, whispering that maybe, just maybe, Rabbi Nachman was their Messiah.

His beard was long and red like his sidelocks, which he curled meticulously. His disciples copied everything they could about their Rebbe, whom they called a tzaddik — a holy man.

They did this because nobody had seen so many of the swirling dead who invisibly surround us as he had, because nobody had been to the land of Israel, as he had, because nobody, in all Ukraine, told stories in mesmerising Yiddish as he did.

Rabbi Nachman died in 1810. "Everything the Messiah can do for Israel . . . I can do too," he sobbed, "only the Messiah can achieve it." His Hasids, or pious ones, wailed as his eyes glazed over. The tzaddik had seemed poised to make a great revelation to the Jews. Hasids on horseback had galloped through Ukraine, shouting to the villagers that a wonder was about to be revealed.

Then a curse descended. Nachman's children began to die. His lungs filled with disease and water. "You see a great tree of wisdom but my roots are in Hell," he shouted at his scribe. He burnt the mystical scrolls he worked on. He grew weaker. Barely able to walk, Nachman trekked with devoted Hasids to the village of Uman to die. He was 38.

In death the Rabbi was a tragic figure. Blinking out of a broken body, he saw his minions dancing around him. Nachman believed he had the soul of the Messiah. But he had achieved for his people — both socially and politically — precisely nothing.

He left behind obsessive writings about the dangers of masturbation, but also fables so enchanting when read in lilting Yiddish they can even induce a state of trance. He left the cryptic, frightening idea that we live in the universe of an "absent God". Nachman's writings are so fresh, yet so obscure. Read in a certain light, it would seem the Rabbi died knowing that the innermost secret of the mystical Kabbalah was that there is no God at all — he is merely what they call a "social construct", that God must constantly be created through chanted confessions and ecstatic prayer.